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1.
Let Δ(x) denote the error term in the Dirichlet divisor problem, and E(T) the error term in the asymptotic formula for the mean square of . If E *(t)=E(t)-2πΔ*(t/2π) with , then we obtain
and
It is also shown how bounds for moments of | E *(t)| lead to bounds for moments of .  相似文献   

2.
Let τ(n) be the Ramanujan τ-function, x ≥ 10 be an integer parameter. We prove that
We also show that
where ω(n) is the number of distinct prime divisors of n and p denotes prime numbers. These estimates improve several results from [6, 9]. Received: 23 November 2006  相似文献   

3.
We consider the problem
where Ω is a bounded smooth domain in , 1  <  p< + ∞ if N = 2, if N ≥ 3 and ε is a parameter. We show that if the mean curvature of ∂Ω is not constant then, for ε small enough, such a problem has always a nodal solution u ε with one positive peak and one negative peak on the boundary. Moreover, and converge to and , respectively, as ε goes to zero. Here, H denotes the mean curvature of ∂Ω. Moreover, if Ω is a ball and , we prove that for ε small enough the problem has nodal solutions with two positive peaks on the boundary and arbitrarily many negative peaks on the boundary. The authors are supported by the M.I.U.R. National Project “Metodi variazionali e topologici nello studio di fenomeni non lineari”.  相似文献   

4.
We consider the following semilinear elliptic equation with singular nonlinearity:
where and Ω is an open subset in . Let u be a non-negative finite energy stationary solution and be the rupture set of u. We show that the Hausdorff dimension of Σ is less than or equal to [(n−2) α+(n+2)]/(α +1).  相似文献   

5.
Let Δ(x) denote the error term in the Dirichlet divisor problem, and E(T) the error term in the asymptotic formula for the mean square of . If with , then we obtain
. We also show how our method of proof yields the bound
, where T 1/5+εGT, T<t 1<...<t R ≤2T, t r +1t r ≥5G (r=1, ..., R−1).  相似文献   

6.
We establish a priori bounds for positive solutions of semilinear elliptic systems of the form
where Ω is a bounded and smooth domain in . We obtain results concerning such bounds when f and g depend exponentially on u and v. Based on these bounds, existence of positive solutions is proved. Dedicated to Felix Browder on the occasion of his 80th birthday  相似文献   

7.
In this paper, we discuss the moving-average process Xk = ∑i=-∞ ^∞ ai+kεi, where {εi;-∞ 〈 i 〈 ∞} is a doubly infinite sequence of identically distributed ψ-mixing or negatively associated random variables with mean zeros and finite variances, {ai;-∞ 〈 i 〈 -∞) is an absolutely solutely summable sequence of real numbers.  相似文献   

8.
We show that if μ is a finite Borel measure on the complex plane such that
for μ-a.e. , then μ must be the addition of some point masses, plus some measure absolutely continuous with respect to arc length on countably many rectifiable curves, plus another measure with zero linear density. We also prove that the same conclusion holds if instead of the condition μ-a.e. one assumes as -a.e. Partially supported by grants MTM2004-00519 and Acción Integrada HF2004-0208 (Spain), and 2001-SGR-00431 (Generalitat de Catalunya). Received: July 2005 Accepted: October 2005  相似文献   

9.
For a trigonometric series
defined on [−π, π) m , where V is a certain polyhedron in R m , we prove that
if the coefficients a k satisfy the following Sidon-Telyakovskii-type conditions:
Translated from Ukrains’kyi Matematychnyi Zhurnal, Vol. 60, No. 5, pp. 579–585, May, 2008.  相似文献   

10.
In the present paper, the following Dirichlet problem and Neumann problem involving the p-Laplacian
((1.λ))
and
((2.λ))
are studied and some new multiplicity results of solutions for systems (1.λ) and (2.λ) are obtained. Moreover, by using the KKM principle we give also two new existence results of solutions for systems (1.1) and (2.1). This Work is supported in part by the National Natural Science Foundation of China (10561011).  相似文献   

11.
We investigate the boundary growth of positive superharmonic functions u on a bounded domain Ω in , n ≥ 3, satisfying the nonlinear elliptic inequality
where c >  0, α ≥ 0 and p >  0 are constants, and is the distance from x to the boundary of Ω. The result is applied to show a Harnack inequality for such superharmonic functions. Also, we study the existence of positive solutions, with singularity on the boundary, of the nonlinear elliptic equation
where V and f are Borel measurable functions conditioned by the generalized Kato class.  相似文献   

12.
In this paper we prove that any residue class λ modulo a large prime number p can be represented in the form
for some positive integers m1, n1,... ,m5, n5 of the size O(p27/28). This improves one of the results from [6] on representability of λ modulo p in the form
with . We also prove that any residue class modulo p can be represented in the form with . This improves the result of [7]. Received: 27 March 2006  相似文献   

13.
Solutions of elliptic problems with nonlinearities of linear growth   总被引:1,自引:0,他引:1  
In this paper, we study existence of nontrivial solutions to the elliptic equation
and to the elliptic system
where Ω is a bounded domain in with smooth boundary ∂Ω, , f (x, 0) = 0, with m ≥ 2 and . Nontrivial solutions are obtained in the case in which the nonlinearities have linear growth. That is, for some c > 0, for and , and for and , where I m is the m × m identity matrix. In sharp contrast to the existing results in the literature, we do not make any assumptions at infinity on the asymptotic behaviors of the nonlinearity f and . Z. Liu was supported by NSFC(10825106, 10831005). J. Su was supported by NSFC(10831005), NSFB(1082004), BJJW-Project(KZ200810028013) and the Doctoral Programme Foundation of NEM of China (20070028004).  相似文献   

14.
Abstract  Let Ω be the unit ball centered at the origin in . We study the following problem
By a constructive argument, we prove that for any k = 1, 2, • • •, if ε is small enough, then the above problem has positive a solution uε concentrating at k distinct points which tending to the boundary of Ω as ε goes to 0+.  相似文献   

15.
We consider one-dimensional difference Schr?dinger equations with real analytic function V(x). Suppose V(x) is a small perturbation of a trigonometric polynomial V 0(x) of degree k 0, and assume positive Lyapunov exponents and Diophantine ω. We prove that the integrated density of states is H?lder continuous for any k > 0. Moreover, we show that is absolutely continuous for a.e. ω. Our approach is via finite volume bounds. I.e., we study the eigenvalues of the problem on a finite interval [1, N] with Dirichlet boundary conditions. Then the averaged number of these Dirichlet eigenvalues which fall into an interval , does not exceed , k > 0. Moreover, for , this averaged number does not exceed exp , for any . For the integrated density of states of the problem this implies that for any . To investigate the distribution of the Dirichlet eigenvalues of on a finite interval [1, N] we study the distribution of the zeros of the characteristic determinants with complexified phase x, and frozen ω, E. We prove equidistribution of these zeros in some annulus and show also that no more than 2k 0 of them fall into any disk of radius exp. In addition, we obtain the lower bound (with δ > 0 arbitrary) for the separation of the eigenvalues of the Dirichlet eigenvalues over the interval [0, N]. This necessarily requires the removal of a small set of energies. Received: February 2006, Accepted: December 2007  相似文献   

16.
Assuming a quasi Generalized Riemann Hypothesis (quasi-GRH for short) for Dedekind zeta functions over Kummer fields of the type we prove the following prime analogue of a conjecture of Erd?s & Pomerance (1985) concerning the exponent function fa(p) (defined to be the minimal exponent e for which ae ≡ 1 modulo p):
((‡))
where
The main result is obtained by computing all the higher moments corresponding to ω(fa(p)), and by comparing them, via the Fréchet-Shohat theorem, with estimates due to Halberstam concerning the moments of ω(p − 1). Received: 25 October 2004; revised: 12 February 2005  相似文献   

17.
Let Ω be a smooth bounded domain of with N ≥ 5. In this paper we prove, for ɛ > 0 small, the nondegeneracy of the solution of the problem
under a nondegeneracy condition on the critical points of the Robin function. Our proof uses different techniques with respect to other known papers on this topic.  相似文献   

18.
Let be the generalized integers n j associated with a set of generalized primes p i in Beurling’s sense. On the basis of the general mean-value theorems, established in our previous work, for multiplicative function f(n j ) defined on , we prove extensions, in functional form and in mean-value form, of the Elliott–Daboussi theorem to high order mean-values. For the main result, let α,ρ, and τ be positive real constants such that α > 1,ρ≥1 and . Then a multiplicative function f satisfies the following conditions, with some constant , (1) All four series
converge and (2)
if and only if the order τρ mean-value
exists with and the limit
exists with . The proof is deduced from an intrinsic connection between m f and . An erratum to this article can be found at  相似文献   

19.
In this paper, the existence “in the large” of time-periodic classical solutions (with period T) is proved for the following two dissipative ε-approximations for the Navier-Stokes equations modified in the sense of O. A. Ladyzhenskaya:
(1)
(1)
and the following two dissipative ε-approximations for the equations of motion of the Kelvin-Voight fluids: satisfying the free surface conditions on the boundary ϖΩ of a domain Ω⊂R3:
. The free term f(x, t) in systems (1)–(4) is assumed to be t-periodic with period T. It is shown that as ε→0, the classical t-periodic solutions (with period T) of Eqs. (1)–(4) satisfying the free surface conditions (5) converge to the classicat t-periodic solutions (with period T) of the Navier-Stokes equations modified in the sense of O. A. Ladyzhenskaya and to the equations of motion of the Kelvin-Voight fruids, respectively, satisfying the boundary condition (5). Translated fromZapiski Nauchnykh Seminarov POMI, Vol. 210, 1994, pp. 109–124. Translated by N. S. Zabavnikova.  相似文献   

20.
Let P(n) denote the largest prime factor of an integer n (2), and let N (x) denote the number of natural numbers n such that 2 n x, and n does not divide P(n)!. We prove that
where (u) is the Dickman-de Bruijn function. In terms of elementary functions we have
thereby sharpening and correcting recent results of K. Ford and J.-M. De Koninck and N. Doyon.  相似文献   

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